Hello. I was wondering if anyone knew of some tutorials for a beginner
who doesn't have a modeller. I am running linux and I tried a few of the
modellers (Behemot, Giram, etc.) but most of them required high-quality
video cards and Mesa/OpenGL type of stuff and I'm not on such a great
computer. So I want to become competent creating scenes only from code,
but I am having difficulties.

In the official POV-Ray docs, the explanation on Bicubic Patch Objects
uses "Moray" -- which I can't use. I tried to create a few objects
typing in my own points, but it is _extremely_ time consuming (I was
trying to make it wrap around and connect). My friend told me that is
would have taken only a few minutes to do that in a modeller. Doh!

So I was wondering if anyone know of some hand-code *ONLY* tutorials.
I don't know if they exist, or even if anyone can produce scenes with
hand-code as fast as with, say, 3DStudio MAX, but I'd like to find out.
When I look at a lot of comments by people who create scenes, it seems
like they all use a modeller to produce things fast (which is what I'd
like to do... i don't have the patience for picking points and rendering
every 0.01 change so many times). But I do have enough patience to learn
it, if the results of a hand-coded scene and a modelled scene are the
same and take up the same amount of time.

Also, please tell me if I'm posting to the right newsgroup. I didn't
want to cross post everywhere.

Thanks! - Another New Povray User, Takahiro (tho### [at] mailusacom)

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Takahiro Horie wrote:
> 
> Hello. I was wondering if anyone knew of some tutorials for a beginner
> who doesn't have a modeller. I am running linux and I tried a few of the
> modellers (Behemot, Giram, etc.) but most of them required high-quality
> video cards and Mesa/OpenGL type of stuff and I'm not on such a great
> computer. So I want to become competent creating scenes only from code,
> but I am having difficulties.

Not to be too critical, but I'm not completely enamoured with any of the
modelers that run in Linux either.

> In the official POV-Ray docs, the explanation on Bicubic Patch Objects
> uses "Moray" -- which I can't use. I tried to create a few objects
> typing in my own points, but it is _extremely_ time consuming (I was
> trying to make it wrap around and connect). My friend told me that is
> would have taken only a few minutes to do that in a modeller. Doh!

Bicubic patches are like that.

> So I was wondering if anyone know of some hand-code *ONLY* tutorials.
> I don't know if they exist, or even if anyone can produce scenes with
> hand-code as fast as with, say, 3DStudio MAX, but I'd like to find out.
> When I look at a lot of comments by people who create scenes, it seems
> like they all use a modeller to produce things fast (which is what I'd
> like to do... i don't have the patience for picking points and rendering
> every 0.01 change so many times). But I do have enough patience to learn
> it, if the results of a hand-coded scene and a modelled scene are the
> same and take up the same amount of time.

Quick summary: some primitives work well when modeling by hand (any sort
of quadric surface, for instance).  Others are really ugly by hand and
pretty much require a modeler. Personally, I've done lathes, blobs, and
cubic surfaces by hand, but only after some messing around with graph
paper.  I haven't done anything remotely representational with the
hairier primitives.  If you're trying to model anything more complicated
than a teapot, use a different primitive.  If you're determined to model
bicubic patches by hand, it would serve you well to do a bunch of
background reading on the subject (Mortenson, _Geometric Modeling_ comes
to mind).  I'm afraid I don't know of any tutorials, but anything on the
mathematics of bicubic patches would be of potential use, while anything
on how to use a particular modeler will obviously be useless.

-Mark Gordon

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Takahiro Horie <tho### [at] ucdavisedu> wrote:
: In the official POV-Ray docs, the explanation on Bicubic Patch Objects
: uses "Moray" -- which I can't use. I tried to create a few objects
: typing in my own points, but it is _extremely_ time consuming (I was
: trying to make it wrap around and connect). My friend told me that is
: would have taken only a few minutes to do that in a modeller. Doh!

  I think that you should forget bicubic patches for now and concentrate
on the other primitives. Bicubic patches are not intended to be created
by hand (and I don't know of anyone who is able to do it).
  Usually bicubic patches are made with a program, either modelling it
with a mouse or calculating it from a mathematical formula. The latter
one is quite easy to do with povray itself (I have done it), but requires
a bit of knowledge about math and about how bicubic patches work.

: So I was wondering if anyone know of some hand-code *ONLY* tutorials.
: I don't know if they exist, or even if anyone can produce scenes with
: hand-code as fast as with, say, 3DStudio MAX, but I'd like to find out.

  I think that it depends on the scene. I think that an expert modeller
user can create almost any scene (which is possible to do with a modeller)
faster than typing the code.
  However, making the scene by hand is not that hard. You only need practice
and more practice. I make almost all of my scenes by hand and seldom use a
modeller. I have learnt everything from the povray documentation. I have not
needed any 3rd party tutorial.
  There are some advantages of making the scene by hand: You can create lots
of mathematical shapes and arrangement of objects which are completely
impossible to do with modellers (unless they support some kind of scripting
language). You can also use all of the great include files around there,
like at http://www.geocities.com/SiliconValley/Lakes/1434/

: Also, please tell me if I'm posting to the right newsgroup. I didn't
: want to cross post everywhere.

  Perhaps povray.newusers could be better?

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Nieminen Juha wrote:

>   I think that you should forget bicubic patches for now and concentrate
> on the other primitives. Bicubic patches are not intended to be created
> by hand (and I don't know of anyone who is able to do it).

Ron Parker does it but I don't know how.

As far as tutorials look no further than the povray.org tutorial links
section - http://www.povray.org/links/3D_Tutorials/POV-Ray_Tutorials/

-- 
Wishing you Seasons Greetings, A Merry Christmas, and A Happy New Year !

Ken Tyler -  1200+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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In article <3860B28E.93334A63@pacbell.net>, lin### [at] povrayorg 
wrote:

> Ron Parker does it but I don't know how.

I have done hand coding of patches, but not with anything complex. 
Probably one of the two primitives I would use a modeller for(with the 
other being large meshes, although I can do small ones by hand). Hmm, 
actually, that isn't quite right, I do use the graphical spline editor 
in MacMegaPOV for lathe, sor, prism, etc objects. Does that count as a 
modeller?

All of the primitives can be hand coded, but the bicubic patch is 
usually done with a modeller. Of course, with the additions to the POV 
language of loops, conditionals, file I/O, and especially macros, you 
can generate the bicubic patches within the POV file.

One thing that may help: as I remember, the only easy way to get patches 
to tile is to overlap them. Imagine dividing them into 9 squares, the 
outermost ring of squares should overlap the surrounding patches, with 
the control points in the same position(did that make any sense?).

 ___________ _______
|   |   |   |   |   |
| - | - | * | + | + |
 ___________ _______
|   |   |   |   |   |
| - | - | * | + | + |
 ___________ _______
|   |   |   |   |   |
| - | - | * | + | + |
 ___________ _______

Squares with a - are in patch A, with a + are in patch B, with a * 
belong to both patches.
Also take a look at the scene description language reference in the 
documentation, it should be in section 4.5.2.1.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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Nieminen Juha wrote:

>   I think that you should forget bicubic patches for now and concentrate
> on the other primitives. Bicubic patches are not intended to be created
> by hand (and I don't know of anyone who is able to do it).

I don't even know anybody who's able to make non-trivial
meshes with smooth_triangles.  However, while it's really
difficult for people to build bicubic patches and smooth_
triangles, it's really easy for modelers to make them, while
it's really hard for modelers to generate some of the other
primitives (at least to do it well).

Stick with the things that are easy for people.  There's
*plenty* of them in POVRay.
--
Bob Crispen
crispen at hiwaay dot net
What we're looking for: destinations.
What we end up getting: journeys.

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Hi

I have made wings of hand coded bicubic patches and once I got the hang of
it it wasn't too slow.

But you can make most things using simple primitives and csg.

Have a look at the IRTC entries and the code submitted with them you can
learn a huge amount from that.

These newsgroups are also a wonderful source of ideas, tips and info.

Finally, try SPatch, Uncle Ken will give you the URL, mind you I'm not sure
if it'll work on Linux.

Mick

--
*************************************************************
Have a merry Christmas and a happy new year.
 Please visit my web site at:-
       http://www.minda.swinternet.co.uk/index.htm

*************************************************************
Bob Crispen <cri### [at] hiwaaynet> wrote in message
news:386165F0.DAABA73D@hiwaay.net...
> Nieminen Juha wrote:
>
> >   I think that you should forget bicubic patches for now and concentrate
> > on the other primitives. Bicubic patches are not intended to be created
> > by hand (and I don't know of anyone who is able to do it).
>
> I don't even know anybody who's able to make non-trivial
> meshes with smooth_triangles.  However, while it's really
> difficult for people to build bicubic patches and smooth_
> triangles, it's really easy for modelers to make them, while
> it's really hard for modelers to generate some of the other
> primitives (at least to do it well).
>
> Stick with the things that are easy for people.  There's
> *plenty* of them in POVRay.
> --
> Bob Crispen
> crispen at hiwaay dot net
> What we're looking for: destinations.
> What we end up getting: journeys.

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